Association between past exposure to fine particulate matter (PM2.5) and peptic ulcer: A cross-sectional study in eastern China.

Ambient fine particulate matter (particle diameter < 2.5 µm, or PM2.5) is a major public health concern in China. Exposure to PM2.5 has been associated with a wide range of adverse health outcomes. The current study aimed to estimate the association between exposure to PM2.5 and the risk of peptic ulcer diseases (PUDs). We conducted a hospital-based cross-sectional study of seven major cities in Zhejiang Province, China (combined population > 57 million people), which included a total of 647,092 subjects who underwent gastroscopy examination (86,852 subjects were diagnosed with PUDs) recorded in 13 large hospitals from 2014 to 2018. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the relationship between PM2.5 and PUDs, including duodenal ulcers (DUs) and gastric ulcers (GUs). The overall estimated OR (95% CI) associated with every 10-µg/m3 increase in the 1-month average PM2.5 before the detection of PUDs was 1.050 (95% CI: 1.038, 1.063). The association between PM2.5 concentration and the prevalence of PUDs tended to be attenuated but remained significant when considering different exposure periods (OR = 1.030, 95% CI = 1.018-1.043 for the 3-month moving average; OR = 1.020, 95% CI = 1.005-1.037 for the 6-month moving average). Stronger associations were observed for DUs than GUs. The observed positive association of PM2.5 exposure with PUDs remained significant in the two-pollutant models after adjusting for other air pollutants. Our findings could provide scientific evidence for a more general adverse role of air pollution on PUDs.